In recent years, regarding terminal apparatuses such as mobile phones, smartphones, personal digital assistants (PDAs), and mobile personal computers (PCs), the size of the displays thereof has been increased. As the size of the display of such a terminal apparatus is increased as mentioned above, the visibility and operability are improved. Meanwhile, the current consumption increases. Accordingly, a problem that the time period for which the terminal apparatus is used decreases occurs.
In order to avoid the above-mentioned problem, in terminal apparatuses of the related art, a function of setting a lighting time period of a backlight in advance is implemented. However, when this function is used, in such a terminal apparatus, for example, when the lighting time period is set to be short, the backlight is automatically turned off although a user is looking at a display. In contrast, when the lighting time period is set to be long, in the terminal apparatus, the backlight is continuously turned on although the user is not looking at the display. Accordingly, the power is wastefully consumed.
For such an issue, among the terminal apparatuses of the related art, there is a terminal apparatus in which a function of turning on and off the backlight in accordance with an inclination obtained using an acceleration sensor is implemented. By using this function, performing control so that the backlight of the display is not turned off when the user is holding the terminal apparatus in his or her hand and looking at the display is made possible.
Japanese Laid-open Patent Publication No. 2011-142497 is an example of the related art.
However, in the terminal apparatus of the related art, when the function of performing control so that the backlight is turned on and off in accordance with the inclination of the terminal apparatus is used, this causes the acceleration sensor to continuously operate. Accordingly, a current of about 200 μA is continuously consumed. Thus, in the terminal apparatus of the related art, the continuous operation of the acceleration sensor is not desired.